Diving
Swim out to the reef from the dive rock with your diving kit, or dive deeper from Captain Brine's submarine on Sundays.
You need all three pieces of diving kit (mask, fins and tank), which Captain Brine gives you, one a Sunday, for helping patch his submarine.
With the kit, swim out from the dive rock on the east beach to the shallows any day the sea isn't rough. On Sundays, diving from the submarine reaches the drop-off and the wreck, where you may meet Purrl.
On the shore and the reef
Common starfishTide pools · dawn, dusk
Hermit crabTide pools · dawn, dusk
Purple sea urchinTide pools · dawn, dusk
NudibranchTide pools · dawn, dusk · April to September
Giant clamThe reef · any time
Spiny lobsterThe reef · any time
Gold doubloonMabel pays 1,200
Ship's bellMabel pays 1,400
Black pearlMabel pays 3,000
Message in a bottleMabel pays 400